The public's interest in renewable energy sources such as biofuels is higher than ever. A lot of this interest in biofuels can be attributed to the desire to lessen America's dependence on imported crude oil. The price of crude oil has fluctuated at a high level recently, and there are frequent tensions with many oil-producing countries. During 2005, U.S. crude oil reached highs of nearly $71 a barrel in August, up from $43 at the beginning of the year. It appears unlikely that prices will stabilize in 2006, given the continued unrest in Iraq and simmering tensions with Iran. Iran is the second largest crude oil producer in OPEC and holds 10% of the world's proven oil reserves. Iran recently warned that crude oil prices would soar if Iran were subjected to economic sanctions in response to its nuclear program. Gasoline has become relatively expensive for American drivers, recently reaching prices of over three dollars per gallon. American motorists have been frustrated by these relatively high gasoline prices, especially over the summers of 2004 and 2005.
Interest in biofuels can also be attributed to public awareness regarding pollution and environmental hazards from the consumption of fossil fuels. The burning of fossil fuels such as petroleum-based fuels, coal and natural gas causes a release of pollutants that may increase global climate change, acid rain, and ozone problems. Fossil fuels are not considered renewable energy sources, as they are the result of organic material being covered by successive layers of sediment over the course of millions of years.
Most cars and trucks on the road today are fueled by gasoline and diesel fuels. These fuels are produced from crude oil, which is a non-renewable fossil fuel. Non-renewable fuels depend on resources that will eventually run out. Renewable energy sources, in contrast, are constantly replenished and will not run out. One type of renewable resource is biomass, which includes plants and organic wastes that can be converted to fuels, chemicals, and other materials. Biomass can be used as solid fuels, or can be converted into liquid or gaseous forms, for the production of electric power, heat, chemicals, or fuels.
Government agencies and corporations in the energy and transportation industries continue to search for and develop renewable energy sources. The U.S. Department of Energy Biomass Program develops technology for conversion of biomass (plant-derived material) to fuels, chemicals, materials and power, so as to reduce dependence on foreign crude oil and foster growth of biorefineries. Biomass can provide a renewable alternative for liquid transportation fuel. The use of biomass would aid rural economies, decrease America's dependence on imported crude oil and reduce pollution.
Ethanol is currently used as a biofuel, most commonly as a fuel component with gasoline for automotive use. In fact, a significant proportion of gas purchased at the pump contains about 10 or 15% ethanol. Ethanol has been widely used as a fuel component in gasoline for about 30 years. Its use as a fuel component was initially motivated by problems with petroleum supplies in the 1970's, as well as political pressure to reduce American dependence on imported crude oil. The use of ethanol was also motivated by a desire to increase the demand for agricultural products such as corn. Ethanol can be obtained by fermentation of hydrolyzed starch, which is obtained by the processing of corn and other agricultural crops.
One of the challenges in getting biofuels to replace fossil fuels has been that the cost of creating biofuels has been higher than the cost of traditional petroleum exploration, production and refining. Another challenge has been that significant energy is required to create a BTU of biofuel, perhaps more than biofuel itself produces in some cases. However, such challenges may be met or reduced (at least in part) by increased crop yield due to biotechnology, improved biomass refinery methods, and increased petroleum costs.
Despite those challenges, use of biofuels in the United States had steadily increased, and the U.S. Department of Energy has set goals to promote the further development and use of biofuels. Among those goals are that by the year 2020, ten percent of transportation fuel will be supplied by biomass, and five percent of industrial and utility power demands will be supplied by biopower.
Ethanol is not the only biofuel that is used commercially. Another is biodiesel, which is currently used in diesel engines. Biodiesel is made by transforming animal fat or vegetable oil with alcohol and can be directly substituted for diesel, either as neat fuel (B100) or as an oxygenate additive (typically 20%-B20). B20 earns credits for alternative fuel use and does not require the purchase of a new vehicle. In Europe, biodiesel is usually made from rapeseed (canola) oil, while in the United States, biodiesel is usually made from soybean oil.
Despite advances in the development of ethanol and biodiesel as biofuels, there remains a need for continued development of biofuels and fuel components from biomass which can be produced relatively easily and inexpensively. It would be highly desirable to identify new fuels and fuel components developed from biomass, including fuels and fuel components having a cost advantage with respect to existing biofuels.